Box tab gluer



Sept. 12, 1967 l D. ADAMsI-:TAL 3,340,849

l' BQX TAB GLUER Filed Feb. 25, 1965 5 sheets-sheet 1 D. ADAMS ETAL BoxTAB GLUER sept. 12, 1967 3 Sheets-Sheet Filed Feb. 25, 1965 INVENTORS.

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SePt- 12, 1967 D. ADAMS ETAL 3,340,849

I BOX TAB GLUER Filed Feb. 25, 1965 3 Sheets-shew. s

INVEN'TORJ)l @An/1.o Hon/w 5 JOHN C?. Han/w 5 irme/m6,.

UnitedStates Patent O 3,340,849 BOX TAB GLUER David Adams, 6658 N. 91stSt., Milwaukee, Wis. 53224, and John Q. Adams, Stephenson, Mich. 49887Filed Feb. 25, 1965, Ser. No. 441,951 12 Claims. (Cl. 118-246) ABSTRACTOF THE DISCLOSURE The disclosure relates to a box tab gluer having avreservoir kept full of glue by a glue source which imposes Thisapplication is a continuation-in-part of our copending application Ser.No. 263,223, filed Mar. 6, 1963, now abandoned.

This invention relates to a box tab gluer.

The embodiments of the invention shown for exemplication hereinconstitute various forms of attachment for a box making machine. Ingluers typically embodying the invention, there is a source of glueunder pressure and a glue reservoir having a glue applying rollerexposed thereto. A box tab is passed over the roller which picks up gluefrom the reservoir and deposits it on the tab. There is a gap betweenthe roller and the wall of the reservoir. Accordingly, the gap issubject to the pressure of the glue source which tends to cause the glueto flow through the gap. K

According to the present invention, however, the glue roller is poweredand its periphery is rotated toward the gap to develop sufficientfriction with the glue in the gap to impose back pressure on the glue inthe gap and counteract the pressure of the glue source, thus to precludeglue ow through the gap. As long as the roller periphery continues torotate toward the gap, glue leakage will not occur.

The present invention eliminates the need for gluetight seals laroundthe roller.

In the gluer of the present invention, the glue reservoir and the glueapplying roller are interposed between the inside and outside tabs ofthe box blank which are normally folded in overlapping relation.Accordingly, these parts function to spread and support the tabs inspaced apart relation, as glue is applied to one of the tabs.

In some embodiments of the invention, the roller and reservoir aretapered toward the folded connection or joint between the outside taband the box blank, thus to better conform to the shape of the box blankin its spread apart relationship.

Other objects, features and advantages of the invention will appear fromthe following disclosure in which:

FIG. 1 is a vertical section taken through one form of gluer embodyingthe invention, this section being taken along the line 1--1 of FIG. 2.-p

FIG. 2 is a vertical section transverse to that of FIG. 1, and takenalong the line 2 2 of FIG. 3.

FIG. 3 is a plan view of the gluer aforesaid.

FIG. 4 is an enlarged fragmentary cross section showing details of theglue-applying roller in association with the glue reservoir.

FIG. 4a is a fragmentary cross section taken along the line 4a-4a ofFIG. 3. v

FIG. 4b is a fragmentary cross section taken along the line 4b-4b ofFIG. 3.

FIG. 5 is a vertical section taken through another form Patented Sept.12, 1967 of the gluer embodying the invention, this section being alongthe line 5-5 of FIG. 6.

FIG. 6 is a vertical cross section transverse to that of FIG. 5, andtaken along the line 6-6 of FIG. 7.

FIG. 7 is a plan View of the gluer embodiment shown in FIGS. 5 and 6.

FIG. 8 is -an enlarged fragmentary cross section of the roller andreservoir of the embodiment shown in FIGS. 5 through 7.

FIG. 9 is a fragmentary cross section taken along the line 9-9 of FIG.6.

FIG. 10 is a vertical section taken through a modified form of gluerembodying the invention in which the reservoir and roller are taperedtoward the folded connection of the outside tab to the box blank and inwhich the roller applies glue to the inside t-ab.

FIG. l1 is a vertical section taken through another form of gluerembodying the invention in which the reservoir and roller are taperedtoward the folded connection of the outside tab to the box blank and inwhich the glue is applied to the undersurface of the outside tab.

FIG. 12 is a perspective view of the tapered roller incorporated in theembodiments of FIGS. 10 and 1l.

Like parts in the several views are given the same reference characters.

Although the disclosure hereof is detailed and exact to enable thoseskilled in the art to practice the invention, the physical embodimentsherein disclosed merely exemplify the invention which may be embodied inother specific structure. The scope of the invention is defined in theclaims appended hereto.

The gluer shown in FIGS. l-4 may conveniently be attached by bracket 11to beam 12 of a conventional `box making machine. The embodiment shownin these figures is adapted to lay strips or beads of glue on the insidetab 13 of the corrugated cardboard box blank indicated generally byreference character 14. The box blank 14 has an outsidetab 15, which,after inside tab 13 has been glued, will be pressed thereagainst by thetraveling belts 16, 17, to form the manufacturers joint of the boxblank.

Bracket 11 suspends the gluer 18 which consists of a glue reservoir orsump 19, the otherwise open end of which is almost completely closed byglue applying roller 20. Roller 20' is desirably provided withcircumferential grooves 21 into which glue 22 Ifrom the reservoir 19will be deposited as the roller turns in the direction of Iarrow 38.Reservoir 19 has a bottom wall 25 over the inside surface of whichdoctor blade 26 -is slidably mounted. The blade 26 is adjustable towardsand away from the periphery of roller 20 by turning adjusting screw 27which is threadedly engaged with the fixed nut 28. Ordinarily, thedoctor blade 26 will be adjusted for light scraping contact with theperiphery of the roller 20, thus to limit transfer of glue to the rollerto that which ad'- heres to the grooves 21 thereof. The doctor blade 26closes the space between the reservoir and the peripheral surface of theroller 20` along a rst line which is spaced arcuately around theperipheral surface of the roller from asecond line along which coverplate 29 is spaced from the peripheral surface of the roller.

Reservoir 19 also has a top wall or cover plate 29 which overhangsroller 20. Duct 30 leads from reservoir 19 to a glue supply means suchas storage tank 31. The glue 22 in tank 31 is at a level considerablyhigher than the reservoir 19, thus to supply glue thereto underhydrostatic'pressure. If desired, the tank 31 could be replaced by ahose leading to a remote source of glue under pressure sucient toconstantly replenish glue in reservoir 19.

Cover plate 29 is spaced from the peripheral surface of roller 20 alonga second line which is spaced arcuately around the peripheral surface ofthe roller @from the first line aforesaid. In accordance with thepresent invention, no attempt is made to seal the space betweenreservoir cover plate 29 and the periphery of the glue roller 20. On thecontrary, a space or gap 34 is left therebetween, aS is best shown inFIG. 4. Under these circumstances, the hydrostatic pressure of the gluein tank 31 would ordinarily tend to force the glue to leak through thegap 34.

In accordance with the present invention, however, roller 20 is mountedon ya shaft 35 which may be power driven in the direction of arrow 38,for example, by belt 36 from motor 37 or the like. Accordingly, theperiphery of the roller 20 moves toward and into the gap 34 and againstthe direction in which the glue would otherwise leak therethrough. Thefriction between the roller periphery and the glue creates a backpressure in the gap 34 which counteracts or balances the hydrostaticpressure of the glue in the tank 19 and precludes glue ow or leakagethrough the gap 34. T he back pressure will depend somewhat upon thespecific gravity of the glue, which is ordinarily semi-viscous. Inpractice, sufficient back pressure is developed to preclude leakage ofeven very thin `glue formulations.

The box blank 14 is fed through the gluer 18, as shown in FIGS. 1 and 2.The inside tab 13 and outside tab 15 which are in overlapping relationin the box blank 14 are spread apart by passing on opposite sides (topand bottom) of the reservior 19. Accordingly, the reservoir 19 comprises-means to spread and support the tabs in spaced apart relation whileglue is applied to the surface of one of the tabs, in this case tab 13.The inside tab 13 of the blank 14 passes over the apron 39 and issubject to the light upward bias of leaf spring 41 against the undersur--face of the glue applying roller 20. Apron 39 comprises guide means toguide the tab 13 against roller 20. Roller 20 is driven in the directionof arrow 38 and will deposit beads or ribbons 40 of glue into the upperexposed surface of the tab 13. As aforestated, no glue will ieak throughthe gap 34 by reason of the back pressure developed at this point byrotation of roller 20 in the direction of arrow 28.

After the tab 13 has passed beyond the gluer in the direction of feed asshown by Iarrow 43, the outer tab 15 will be brought into pressureengagement with tab 13 by reason of the traveling belts 16, 17, thus toglue the tabs together and form the manufaeturers joint in the boxblank.

FIGS. -8 show a modified embodiment of the invention in which the beadsor ribbons 40 of glue are applied to the outside tab 15 of the blank 14.Like parts are given the same reference characters as in the embodimentof FIGS. 1-4.

The only substantial difference as between the two embodiments is thatthe glue applying roller 20 has its upper surface exposed to theundersurface of the outer tab 15 and inside tab 13 does not receive anyglue treatment until brought into pressure engagement with tab 15 byreason of the action of the traveling belts 16, 17.

The reservoir 44 is of slightly different construction, in that itsbottom 45 is closed. The top wall or cover plate 46 of the reservoir 44is adjustable on the set screws 47 to function as a doctor blade withrespect to the roller 20. Roller 20 in this instance is rotated in theopposite direction to which it was rotated in the embodiment of FIGS.l-4. Roller shaft 35 is driven by motor 37 through belt 36 vin thedirection of arrow 49. In this instance, the gap 48 through which thehydrostatic pressure of the glue 22 would ordinarily cause leakage isbetween the periphery of the roller 20 and the bottom wall 45 of thereservoir 44. No leakage occurs between the doctor blade and the roller20. Because of the back pressure produced in the gap 48 by reason ofrotation of the roller toward the gap, no leakage occurs through thegap.

A guide means such as wheel 51 is provided to press the outside tab 15downwardly against the roller 20 and insure proper application of thebeads or ribbons of glue 40 to the tab 15.

In both of the embodiments above described, the roller is rotated towarda gap which need not be provided with conventional seals because of theback pressure produced therein as aforesaid. Accordingly, the devicewill not leak, even when there is no box blank in the machine, as longas the roller 20 is rotated in the proper direction to develop backpressure balancing the hydrostatic pressure of the glue source.

FIG. 4a shows an optional Ifeature of all embodiments of the invention.Grooves 60 are formed in the side walls of the reservoir 19 at each endof the roller 20. Grooves 60 have arcuate portions just within the outerperiphery of the roller 20 and have tangential or tail portions 61 whichlead into the reservoir 19. Accordingly, as the roller 20 turns in thedirection of arrow 38, any glue which tends to leak past the ends of theroller is caught in the grooves 60 and is returned to the reservoir 19under pressure of the rotating wheel.

Another optional feature of all embodiments of the invention is shown inFIG. 4b. A spiral groove 62 is formed in each end of the roller 20. Asthe roller turns in the direction of arrow 38 any glue trapped at theends of the roller is carried away from shaft 35 and outwardly to theperiphery of the roller. This keeps the glue out 0f the bearings forshaft 35. This feature also permits some slight end play in the rollerwithout danger of leakage. In a practical embodiment of the inventionthe end play thus allowed exceeds .002 inch.

Another optional but desirable feature of all embodiments of theinvention is shown in FIG. 9, which shows details of the sleeve bearings63, 64 in walls 65, 66 of reservoir 44. A grease fitting 67 is providedfor bearings 63 and grease fitting 68 is provided for bearing 64. Greaseis forced under pressure into the bearings to exclude any glue whichtends to work into the bearings and to act as a barrier to the entry ofglue. After the gluer is used and washed up, charges of grease areforced through each fitting '67, 68. -Enough -grease is used to fill thespace between the end of the roller 20 and the side walls of thereservoir. This prevents the roller from sticking to the walls, when notin operation.

In the embodiments of FIGS. 1 through 9, the roller 20 is cylindricaland the reservoirs 19, 44 have spaced parallel tops and bottoms. FIGS.l0 and l1 show modified embodiments in which the roller is conical inshape and in which the respective reservoirs 81, 82 are taperedoutwardly from the support standard 11 toward the joints 83 on which thesides 84 of the box blank are lfoldably connected to side thereof.Accordingly, the tapered roller 80 and reservoirs 81, 82 have slopedupper surfaces which better conform to the slope of the box blank panels15, 84 which pass over the top of the reservoir. This is particularlyadvantageous where the box blank is narrow, as shown in FIGS. 10 and 11,as compared to a box blank which is wide, as shown in FIGS. 1 and 5. Innarrow box blanks the Ifold line 83 is closer to the gluer. Theconstruction shown in FIGS. l0 and 11 will produce less bending stresseson the box blank than the embodiment shown in FIGS. 1 and 5.

In other respects, the devices shown in FIGS. l0 and 1l are similar inconstruction to those previously described. In the embodiment of FIG.10, the roller 80 applies beads or ribbons of glue to the upper surfaceof inside tab 13. For this purpose, the tab 13 is guided by the apron 39and the pressure of the leaf spring 41 against the undersurface of theroller 80, in much the same manner as is shown in FIGS. 4 and 4a, exceptthat the roller 80 is tapered as aforestated.

In FIG. 11 the relationship between the roller 80 and the reservoir 82is similar to that shown in FIG. 8 (except for the taper of the rollerand the reservoir). A guide wheel 51 presses the outside tab 15 againstthe upper surface of the roller 80. The guide roller 51 is provided withan inclined bearing tube 86 `for its shaft 87.

Respective rollers 80, shown in FIGS. 10 and 11, have drive shafts 88which are inclined as shown in these figures to accommodate for thetaper of the rollers 80. The ends of the shafts have belt pulleys 89 forthe drive belts 90:

As in the previously described embodiments, each roller 80 is desirablyprovided with circumferential grooves 90 which meter the amount of gluedeposited in bands or ribbons, as shown at 40 in FIGS. 4 and 8.Accordingly, the doctor blade may scrape against the ungrooved surfaceof the roller leaving only the glue in the grooves 90 to be applied tothe tab surface. The rollers 80' may also be provided with end spiralgrooves, as shown in FIG. 4b, and the reservoir walls may be providedwith grooves such as 60, 61, as shown in FIG. 4a.

In all embodiments of the invention, the gluer functions to separate andmaintain the tabs 13, 1S in spaced relationship as the glue is appliedby the roller to that surface 0f one or the other of the tabs which willface a corresponding surface of the other tab when the tabs are broughttogether under pressure of the belts 16, 17.

What is claimed is:

1. A box tab gluer for a box blank having inside and outside tabs foldedin said blank in overlapping relation, said gluer comprising:

a glue applying roller having a peripheral surface,

a glue reservoir to which the roller is exposed to pick up gluetherefrom,

said reservoir comprising means to spread and support said tabs inspaced apart relation as glue is applied to one of said tabs,

guide means for guiding one of said box tabs against said peripheralsurface of said roller,

said reservoir having:

a doctor blade substantially closing the space between said reservoirand the peripheral surface along a first line at one side of the roller,

and a wall portion spaced from the peripheral surface along a secondline at another side of the roller to leave a gap between the wallportion and the peripheral surface of the roller along said second line,

said first and second lines being spaced arcuately around the peripheryof said roller,

means to ll said reservoir with glue and including a source ofhydrostatic pressure for the glue in the reservoir to tend to cause saidglue to flow through said gap,

and power means to rotate the periphery of said roller toward said gapto develop suicient back pressure in the glue in said gap to counteractsaid hydrostatic pressure and preclude glue flow through said gap.

2. The gluer of claim 1 in which said source of hydrostatic pressurecomprises a glue tank at a higher elevation than the glue reservoir andcommunicating therewith.

3. The gluer of claim 1 in which said guide means guides the box tabbeneath the roller, said doctor blade being disposed along the bottom ofthe reservoir, said power means rotating the periphery of the rolleraway from the doctor blade, said guide means including means `for urgingthe tab upwardly against the roller.

4. The gluer of claim 1 in which said guide means guides the box tababove the roller, said doctor blade being disposed along the top of theroller, said power means rotating the periphery of the roller away fromthe doctor blade, said guide means including means for urging the tabdownwardly against the roller.

5. The gluer of claim 1 in which an end of the glueapplying roller isprovided with a spiral groove to carry glue toward the roller peripheryas the roller turns.

6. The gluer of claim 1 in which said reservoir has side l walls betweenwhich the roller is disposed, at least one of said walls having a grooveleading in the direction of roll rotation from within the periphery ofthe roller to said reservoir.

7. The gluer of claim 1 in which said reservoir has side walls betweenwhich said roller is disposed, said roller having a shaft and bearingsfor said shaft in said walls, and grease fittings -for said bearings bywhich grease is charged into said bearings.

v8. The gluer of claim 1 in which the peripheral sur- -face of theroller has circumferential grooves in which glue is carried past thedoctor blade.

9. The gluer of claim 1 in which the roller and reservoir are taperedtoward the fold of said outside tab with the box blank.

10. A box tab gluer for a box blank having inside and outside tabsfolded in said blank in overlapping relation, said gluer comprising:

means to spread and support said tabs in spaced apart relation as glueis applied to one of said tabs,

said means comprising a glue applying roller between said tabs andhaving a peripheral surface and a glue reservoir to which the peripheralsurface of the roller is exposed to pick up glue therefrom,

guide means for guiding one of said box tabs against the peripheralsurface of the roller,

said reservoir having:

a doctor blade substantially closing the space between said reservoirand the peripheral surface along a rst line at one side of the roller,

and a wall portion spaced from the peripheral surface along a secondline at another side of the roller to leave a gap between the wallp0rtion and the peripheral surface of the roller along said second line,

said irst and second lines being spaced arcuately around the peripheryof said roller,

means to ll said reservoir with glue and including a source ofhydrostatic pressure for the glue in the reservoir to tend to cause saidglue to flow through said gap,

and power means to rotate the periphery of said roller toward said gapto develop sufficient back pressure in the glue in said gap tocounteract said hydrostatic pressure and preclude glue ow through saidgap.

11. The gluer of claim 10 in which the roller and reservoir are taperedtoward the fold of said outside tab with the box blank.

12. The gluer of claim 11 in which the roller has circumferentialgrooves in which glue is carried past the doctor blade.

References Cited UNITED STATES PATENTS CHARLES A. WILLMUTH, PrimaryExaminer.

L. G. MACHLIN, Assistant Examiner.

1. A BOX TAB GLUER FOR A BOX BLANK HAVING INSIDE AND OUTSIDE TABS FOLDEDIN SAID BLANK IN OVERLAPPING RELATION, SAID GLUER COMPRISING: A GLUEAPPLYING ROLLER HAVING A PERIPHERAL SURFACE, A GLUE RESERVOIR TO WHICHTHE ROLLER IS EXPOSED TO PICK UP GLUE THEREFROM, SAID RESERVOIRCOMPRISING MEANS TO SPREAD AND SUPPORT SAID TABS IN SPACED APARTRELATION AS GLUE IS APPLIED TO ONE OF SAID TABS, GUIDE MEANS FOR GUIDINGONE OF SAID BOX TABS AGAINST SAID PERIPHERAL SURFACE OF SAID ROLLER,SAID RESERVOIR HAVING: A DOCTOR BLADE SUBSTANTIALLY CLOSING THE SPACEBETWEEN SAID RESERVOIR AND THE PERIPHERAL SURFACE ALONG A FIRST LINE ATONE SIDE OF THE ROLLER, AND A WALL PORTION SPACED FROM THE PERIPHERALSURFACE ALONG A SECOND LINE AT ANOTHER SIDE OF THE ROLLER TO LEAVE A GAPBETWEEN THE WALL POR-